1. Technical Field
The present invention relates to a portable telephone having an abbreviated number calling function (or one-touch speed dialing function).
2. Background Art
Generally, a portable telephone can be used for not only communication with a third party but other purposes (e.g., ticket reservations) like a home-use pushbutton telephone. To use the portable telephone for the latter, it is necessary to transmit a calling person's number or a secret identification number for identification. A user can combine such a number with a telephone number to make new telephone number and can register new telephone number into the portable telephone.
Portable telephones are prevailing in recent years. In some companies, each employee is given one portable telephone. In order to delimit a possible communication scope, proposed is a portable telephone which has a limited dialing function which only allows a user to call predetermined third parties having certain abbreviated numbers or "group numbers". One "group number" is assigned to a plurality of abbreviated numbers for an easier utilization of abbreviated numbers.
When a user inputs an abbreviated number to call someone or to confirm a telephone number, the telephone number corresponding to the abbreviated number is displayed. Therefore, it is impossible to hide a telephone number which may represent an access number or password of a computer and should not be known to other persons and the telephone number may be used for evil purpose.
If the portable telephone has a dialing restriction function, it is possible to limit possible calling of a group of several abbreviated numbers to which a group number is assigned, but still impossible to hide telephone numbers corresponding to the abbreviated numbers.
Specifically, when the user refers to an abbreviated number by inputting the group number, a telephone number corresponding to the abbreviated number is displayed together with the abbreviated number. When the user inputs an abbreviated number to refer to the group number, a telephone number corresponding to the abbreviated number is displayed together with the group number. Therefore, the user will see a telephone number which corresponds to the abbreviated number even if the group number is assigned to the abbreviated number and the call with the abbreviated number (speed dialing) is prohibited.